Furnace



-( 3 Sheets-Sheet 1.

- A. BITTER, Jr.

FURNACE. No. 374,999. Patented Dec. 20, 1887;

Q 4 V MM/h (No Model.)

3 Sheets-Sheet 2. A. BITTER, Jr.

FURNACE.

Patented Dec. 20, 1887.

attorney (Nb Model.) a Sheets-Sheet 3.

A. BITTER, Jr.

FURNAGR I No. 374,999. Patented Dec. 20, 1887.

ATTEST INVENTOR:

UNITED STATES PATENT OFFICE.

ANDREW BITTER, JR, OF CHICAGO, ILLINOIS.

FURNACE.

SPECIFICATION forming part of Letters Patent No. 374,999, dated December20, 1887.

Application filed January 10, 1884. Serial No.117.067.

To aZZ whom it may concern.-

Be it known that-I, ANDREW BITTER, J r., a citizen of the United States,and a resident of Chicago, in the county of Cook and State of Illinois,have invented certain new and useful Improvements in Steam-BoilerFurnaces; and I do hereby declare the following to be a full, clear, andexact description of the same, reference being had to the accompanyingdrawings, forming apart of this specification.

The present invention relates more especially to that class of furnacesdescribed in Letters Patent No. 290,270, issued to me Decem' ber 18,1883, for improvement in steam-boiler furnaces; and the objects of thepresent improvement are, first, to afford means for sustaining thevoussoirs or arch-bricks composing the arched furnace-top in properposition against any tendency to undue settling of any one of the samewith relation to another, due to the excessive changes of temperature towhich the furnace-arch is exposed in the present type of furnace second,to provide a cheap and durable means for forming the fuelfeeding pocketsof the furnace, and at the same time furnish an abutment for thesustaining bars or frame of the arch-bricks; third, to furnish means foragitating the fuel within the fuel-pockets, so as to cause the same tofeed faster or slower onto the inclined fire-grates of the furnace;fourth, to afford means whereby the feed-opening or capacity of thefuelpockets can be adjusted, as required, in the regulation of the fire;and, fifth, to providemeans for the introduction of a supply of cold airinto the rear part of the ash-pit and underneath the rear portion of thefire-grates, in order to equalize the temperature in the ash-pit andprevent burning out of the rear end of the fire-grates. I attain suchobjects by the construction of parts illustrated in the accompanyingdrawings, in which Figure 1 is a longitudinal section of a horizontalsteam-boiler furnace to which my improvements are adapted. Fig. 2 is aview, one-half in front elevation and one-half in transverse section,through the furnace-chamber. Fig. 3 is a half-horizontal section atlines a m and w m, respectively, Fig. 2. Fig. 4 is a (No model.)

posing said arch; and Fig. 5, an enlarged detail transverse section ofthe furnace.

Similar letters of reference indicate like parts in the several views.

The present invention relates, mainly, to means for sustaining thefurnace-arch in proper shape, in order to resist in a very perfectmanner the natural tendency to settle, due to the excessive changes oftemperature to which it is exposed. This I attain by the use of metallicarch bars A, extending from abutment to abutment, around which thearch-bricks or voussoirs B are built. (See Figs. 1 and 4.) It ispreferable to make the arch-bars A of an inverted-T shape, yet any othersuitablyshaped bar may be used, as found most de' sirable or convenient,the arch-bricks having recesses b of a shape corresponding to that ofsuch bars. By this construction a double purpose is attained first, aneffective support for the archbricks, and, second, the incasement of thearch bars and the protection of the same from the direct action of thefire. The archbars rest upon flanged abutment-plates G, suitablyattached to the furnace side walls, and it is preferred to so constructthese plates that they will form protecting-linings c for thefuelfeeding pockets D.

The end pocket liner pieces, -c',are made tubular, as shown, so as toform a passage or conduit from the top of the furnace to the interior orfire'chamber ofthe same, thepurpose of such tubular construction beingthreefoldfirst, to introduce a supply of fresh air to promote combustionof the fuel; second, to prevent buckling of the liner by the excessiveheat to which it is exposed, and, third, to conduct back into thefire-chamber any gusts of smoke or gases escaping from the mouths of thefeedingpockets.

In order to prevent the melting or sagging down of the rear portion ofthe fire-grate in this class of furnaces, and which is caused by theexcessive temperature to which such por tion of the grate is exposed, Iemploy the following means to prevent such i nj urions results, to wit:a current of cool air introduced into the rear portion of the ash-pitand immediately underneath the rear portion of the fire grate through aline or passage, E, extending from the front of the furnace horizontallythrough the side walls of the same and arranged as near to the ground aspractical. By this construction the temperature at the rear' end of theash-pit can be brought to a uniform degree with that of the balance ofthe pit and afford a supply of cold air to all parts of the fire-grate,and thus effectually prevent any portion of the same from becomingunduly heated.

To more effectually regulate and control the temperature in theash-pit,I provide said passage E with an adjustable door or damper, e, and alsoprovide an adjustable door or damper, F, preferably of a butterfly form,as shown, in the ash-pit doorway, so that by the regulation of suchdoors or dampers e F the admission of air and the consequent temperatureof the ash-pit can be regulated and controlled as circumstances mayrequire. 7

The amount of fuel contained in the fuelpockets D is controlled by ahinged chokeplate,d, arranged at one side of the same, and which, whenin its down position, as shown in dotted lines in Fig. 5, permits of thepocket being filled to its full capacity with fuel, and when turned toits up position, as shown in full lines in Fig. 5, limits or decreasesthe holding capacity of the pockets in accordance with the use of thefurnace in heavy or light firing.

To agitate and feed the fuel from the feedpocket-s down onto theinclined furnace-grates I provide a semi-rotary shaker or agitator, d,

. to stir up and agitate the fuel, so as to cause it to feed down ontosuch grates, movement being communicated to such shaker by a crank-arm,d", arranged outside of the furnace. 7 I am aware that prior to myinvention it was a common expedient to employ iron girders to form thepier or abutment-points for a series of arches that forms the roof of afur nace or the horizontal partition or floor of a building. I am alsoaware that a supply of heated air has been conducted vertically downthrough the side walls of a furnace and discharged underneath thefire-grates to promote combustion. I therefore do not claim either ofthese features of construction, broadly.

I am further aware that it is not new to tie or brace cylindrical, 850.,walls of grairrbins, &c., by circular or annular tension-bars, as

bricks or voussoirs 13, having recesses b in their sides to receive thearch-bars, in combination with the furnace side walls, essentially asset forth.

8. An arch for furnaces, consisting of shaped arch-bars A,extendin.gfrom abutment to abutment, and arch-bricks B, having recesses bin theirsides, essentially as and for the purpose set forth.

4. An arch for furnaces,provided with fuelfeeding pockets D, thelining-frame of which forms abutments for the arch-supporting bars A,essentially as set forth.

5. In an arch for furnaces,having fuel-feeding pockets D, the endliners,c,made tubular, for the purpose set forth.

6. In a furnace of the form described, the vertical fuel-feeding pocketsD, adapted to carry the fuel down onto the fire-grates and provided witha hinged choke-plate, cl, as described, and for the purpose set fort-h.

7. In a furnace of the form described, the vertical fuel-feeding pocketsD, adapted to conduct the fuel down onto the fire-grates, and providedwith a hinged choke-plate, d, and a semi-rotary agitator, d, asdescribed, and for the purpose set forth.

8. In a furnace, the conduit E, arranged as herein described, andprovided with a damper, 0, in combination with the ash-pit doorwayprovided with a hinged door or damper, F, essentially as set forth.

In testimony whereof witness my hand this 5th day of January, 1884.

ANDREW BITTER, JR.

In presence of ROBERT BURNS, A. CAMPBELL.

